1. Field of the Invention
This invention relates to methods and apparatus for controlling fluid delivery from a spray head having a moving spray nozzle.
2. Background of the Related Art
Showerheads are commercially available in numerous designs and configurations. While many showerheads are designed and sold for their decorative styling, there is a great number of different showerhead mechanisms which are intended to improve or change one or more characteristic of the water spray pattern. Any particular spray pattern may be described by the characteristics of spray width, spray distribution or trajectory, spray velocity, and the like. Furthermore, the spray pattern may be adapted or designed for various purposes, including a more pleasant feeling to the skin, better performance at rinsing, massaging of muscles and conservation of water, just to name a few.
The vast majority of showerheads may be categorized as being either stationary or oscillating and having either fixed or adjustable openings or jets. Stationary showerheads with fixed jets are the simplest of all showerheads, consisting essentially of a water chamber and one or more jets directed to produce a constant pattern. Stationary showerheads with adjustable jets are typically of a similar construction, except that some may allow adjustment of the jet direction, jet opening size and/or the number of jets utilized. For example, a showerhead currently used in typical new residential home construction provides a stationary spray housing having a plurality of spray jets disposed in a circular pattern, wherein the velocity of the spray is adjustable my manually rotating an adjustment ring relative to the spray housing.
These stationary showerheads cause water to flow through its apertures and contact essentially the same points on a user's body in a repetitive fashion. Therefore, the user feels a stream of water continuously on the same area and, particularly at high pressures or flow rates, the user may sense that the water is drilling into the body, thus diminishing the positive effect derived from such a shower head. In order to reduce this undesirable feeling, various attempts have been made to provide oscillating showerheads.
Examples of oscillating showerheads are disclosed in U.S. Pat. Nos. 3,791,584 (Drew et al.), 3,880,357 (Baisch), 4,018,385 (Bruno), 4,944,457 (Brewer), and 5,577,664 (Heitzman). U.S. Pat. No. 4,944,457 (Brewer) discloses an oscillating showerhead that uses an impeller wheel mounted to a gear box assembly which produces an oscillating movement of the nozzle. Similarly, U.S. Pat. No. 5,577,664 (Heitzman) discloses a showerhead having a rotary valve member driven by a turbine wheel and gear reducer for cycling the flow rate through the housing between high and low flow rates. Both of these showerheads require extremely complex mechanical structures in order to accomplish the desired motion. Consequently, these mechanism are prone to failure due to wear on various parts and mineral deposits throughout the structure.
A particularly useful action for a showerhead is referred to as "wobbling." The term "wobbling" may be defined as the motion of a circular member rolling on its edge along a surface following a circular path. A common example of wobbling is what occurs when a coin is spun on its edge over a smooth surface. The coin begins spinning or rotating in an vertically upright position, but as the coin slows, the coin begins to wobble along a circular path having an ever increasing diameter until the coin comes to rest on its face. While a wobbling motion will often be accompanied by some degree of rotation, a wobbling member will have points on its surface which experience a sequence of up and down motions as well.
Most spray heads, whether they are stationary or oscillating, deliver fluids in a predetermined manner. The user is not allowed to effect changes in the fluid delivery characteristics of the spray head, except perhaps increasing or decreasing the fluid flow rate by turning the control valve that communicates fluid to the spray head. One such spray head which actually allows user adjustments between a vibrating mode and a non-vibrating mode is disclosed in U.S. Pat. No. 5,467,927 (Lee). However, spray heads that allow adjustment of other fluid delivery characteristics have not been available.
Therefore, there is a need for an improved spray head or showerhead that allows a user to adjust or control the delivery of fluid. Characteristics of the fluid delivery that would be particularly desirable include the spray width, the spray velocity and spray flow rate. It would be desirable if the spray head were able to deliver water in the desired manner, even at low pressures or flow rates dictated or desirable for water conservation. It would be further desirable if the spray head provided a simple design and construction with minimal restriction to water flow.